Maybe you've seen my article about the 9 Volt Power supply is in the visible scheme using series regulator IC 7809. Many methods to generate DC voltage in power supply with 9VDC outputs result. One of them is to use a zener diode. The use of Zener diodes to produce this voltage can not be applied in a large power, while the inputs that go into the zener diode should not be large, it will make it burn, unless you use a large amperage on the zener diode. Provisions to obtain a stable voltage at the input of the zener should use a resistor after the rectifier voltage source. To apply them to big power transistors must be assisted by. Usually zener placed on the transistor base with the help of resistors, can not be directly from the results of the DC voltage source rectifier transformer. Transformer used in this power supply does not exceed the maximum voltage that should be fed to the diode cathode poles, power transformer least around 500mA-1A.
Zener Diode usually consists of two pole polarity, the pin cathode and anode. The cathode is usually a line to black (or red) on the diode body. In a simple scheme below you can see how the reduction or locking of the output voltage after the rectifier into a DC voltage of 9V. Zener diode code to get this voltage is usually labeled name 9.1V. Sometimes the factory writes power and temperature tolerance, the writing is very small. For mounting Diode’s wire do not reversed, it will result in broken or short circuit occurs at the output. Cathode should get helped by a positive voltage after the resistor, and then the voltage of 9 volts locking occurs at the confluence of the resistor and the cathode to the negative / common.
Zener Diode usually consists of two pole polarity, the pin cathode and anode. The cathode is usually a line to black (or red) on the diode body. In a simple scheme below you can see how the reduction or locking of the output voltage after the rectifier into a DC voltage of 9V. Zener diode code to get this voltage is usually labeled name 9.1V. Sometimes the factory writes power and temperature tolerance, the writing is very small. For mounting Diode’s wire do not reversed, it will result in broken or short circuit occurs at the output. Cathode should get helped by a positive voltage after the resistor, and then the voltage of 9 volts locking occurs at the confluence of the resistor and the cathode to the negative / common.
In the picture below we see a combination of the use of a zener diode with a transistor to generate a large power output. I prefer to use NPN transistors for this circuit. You can use any type NPN transistor origin is related to the characteristics and functions of transistors that we use. Suppose we may use the D313, TIP31 or 2N3055. For this transistor must be given in the form of external cooling heat sink.
